1. Field of the Invention
The field of the present invention concerns the use of animal skins as food treats for canines. These treats may be prepared from a variety of materials such as cow raw hide or pork skins. The process and products of the present invention concern the use of pork skin and the removal of a desired amount of fat from that starting material. The present invention does not concern the use of pork skin for non-dietary purposes, nor does it concern a process for use on pork meat.
2. Description of the Prior Art
Traditionally, canine treats have been made from cow raw hide or pork skin. Raw hide has significant disadvantages in that it is indigestible providing no nutritional value to the animal and is well known for becoming lodged in the animal's throat or digestive tract. Pork skin is a more preferable material for canine treats since it is digestible providing nutritional value to the animal.
Historically, pork skin has been used as a base material for a variety of non-food products such as shoes, gloves, belts and other items. In the manufacture of these types of goods, any fat present in the raw material must be removed and conventional techniques are known that will entirely remove fat from pork skin. However, these known techniques typically involve saturating the pork skin with strong hydrocarbon solvents that will solubilize any fat that is present in the material. Not only do such techniques remove all of the fat that is held within the pork skin, but the use of these solvents renders the pork skin inedible and in some cases toxic. Therefore, there remains a need for a process that will allow for the controlled removal of fat from pork skin and that will not render the pork skin inedible upon completion of the process.
There are also known techniques and processes for the removal of fat from various types of raw meat materials such as beef, fowl, pork and seafood products. U.S. Pat. No. 5,221,554, issued to Gamay, entitled "Process for producing low-fat meat products" is an example. The '554 patent discloses a process in which the meat is comminuted into small particles, typically through grinding, in the presence of water with ionic strength manipulation. The meat in solution is then fractionalized into fatty materials, connective tissues and low fat meat particles. The disclosed process, however, does not address pork skin, the removal of a controlled amount of fat therefrom, or the manufacture of products from that material. Further, the process requires that the meat be broken down into smaller particles in order to remove fat from the meat.
Several other known techniques for removing fat from meat materials include grinding the meat and extruding it through a specially designed heat exchanger as described in U.S. Pat. No. 4,567,050, entitled, "Method for processing meat products"; exposing the meat material to ultraviolet light and comminuting the meat at low temperatures in the presence of edible acids, salts and food phosphates as described in U.S. Pat. No. 4,788,682, entitled "Method of preparing a low-fat, low-cholesterol raw meat product"; introducing a heated unsaturated oil into the material to solubilize the fat for subsequent extraction, as is described in U.S. Pat. No. 4,980,185, entitled "Method for making meat products having a reduced saturated fat and cholesterol content"; and various techniques that comminute the meat, and use heat treatments to separate the fat as illustrated by U.S. Pat. No. 5,762,993, entitled "Process for preparing reduced fat meat". All of these processes are directed at removing a high percentage of the fat from the meat so that it may be used to prepare food products for human consumption that may be characterized as either low in fat or "fat free." These disclosed processes and techniques are not intended for use on pork skin or other animal skin materials but are directed at meat and meat trimmings. They require that the meat used be reduced to smaller particle sizes either through grinding or hand trimming before the disclosed process can be used to remove fat retained in the meat. Further, the operating temperatures discussed in these processes are relatively low so that the taste or texture of the meat is not adversely affected by the fat removal process. These lower operating temperatures are generally too low to effect the removal of fat from animal skin materials such as pork skin. Furthermore, these processes are not designed for and thus, are incapable of removing an incremental amount of fat from animal skin materials such the fat content of the final product may be selected during processing.
Therefore, it is an object of the present invention to provide an all natural process for removing a controlled amount of fat from pork skin rendering it a nutritional material.
It is another object of the present invention to provide a fat removal process that does not require the comminuting or grinding of the animal skin material prior to removing fat therefrom such that the reduced fat material may be subsequently used to produce a greater variety of food and treat products.
It is an additional object of the present invention to provide a process for preparing a variety of treat products that will appeal to canines using the reduced fat pork skin material. These additional products may include simulated bones, chips, twisted products, filled bones, patties, sticks and similar treat products.
It is an additional object of present invention to provide a fat removal process that does not require the use of harsh solvents or chemicals that might otherwise render the pork skin inedible or unfit for consumption.
It is a further object of the present invention that the process may be carried out using conventional materials and equipment, requiring a minimal skill and supervision.